week of the same. For it is in truth the third week, because it begins on the evening of the fourteenth day, and ends on the evening of the one-and-twentieth.
“But since Christ our Passover is sacrificed,(960) and has made the Lord’s day, which among the ancients was called the first day of the week, a solemn day to us for the joy of His Resurrection, the Apostolic tradition has included it in the Paschal festival; yet has decreed that the time of the legal Passover be in no wise anticipated or diminished; but rather ordains, that according to the precept of the law, that same first month of the year, and the fourteenth day of the same, and the evening thereof be awaited. And when this day should chance to fall on a Saturday, every man should take to him a lamb, according to the house of his fathers, a lamb for an house, and he should kill it in the evening, that is, that all the Churches throughout the world, making one Catholic Church, should provide Bread and Wine for the Mystery of the Flesh and Blood of the spotless Lamb ‘that hath taken away the sins of the world;’(961) and after a fitting solemn service of lessons and prayers and Paschal ceremonies, they should offer up these to the Lord, in hope of redemption to come. For this is that same night in which the people of Israel were delivered out of Egypt by the blood of the lamb; this is the same in which all the people of God were, by Christ’s Resurrection, set free from eternal death. Then, in the morning, when the Lord’s day dawns, they should celebrate the first day of the Paschal festival; for that is the day on which our Lord made known the glory of His Resurrection to His disciples, to their manifold joy at the merciful revelation. The same is the first day of unleavened bread, concerning which it is plainly written in Leviticus,(962) ‘In the fourteenth day of the first month, at even, is the Lord’s Passover. And on the fifteenth day of the same month is the feast of unleavened bread unto the Lord; seven days ye must eat unleavened bread. In the first day ye shall have an holy convocation.’